According to Guinness, “The smallest purpose-built cinema is the Cabiria Cine-Cafe which measures 24 m² (258.3 ft²) and has a seating capacity of 18. It was built by Renata Carneiro Agostinho da Silva (Brazil) in Brasilia DF, Brazil in 2008.”

I’m not finding it here in the database. Is is under another name, or do we need to make a submission?

Based on the bottom photo here, the the Bijou may have 18 seats, though 2 can’t be seen so it could be 16: